Re: [PATCH 1/2] completion: move blk_wait_io to kernel/sched/completion.c

[Jens Axboe <axboe@kernel.dk>]

On 4/18/24 8:46 AM, Christoph Hellwig wrote:
> On Thu, Apr 18, 2024 at 08:30:14AM -0600, Jens Axboe wrote:
>> It certainly is a hack/work-around, but unless there are a lot more that
>> should be using something like this, I don't think adding extra core
>> complexity in terms of a special task state (or per-task flag, at least
>> that would be easier) is really warranted.
> 
> Basically any kernel thread doing on-demand work has the same problem.
> It just has an easier workaround hack, as the kernel threads can simply
> claim to do an interruptible sleep to not trigger the softlockup
> warnings.

A kernel thread can just use TASK_INTERRUPTIBLE, as it doesn't take
signals anyway. But yeah, I guess you could view that as a work-around
as well.

Outside of that, mostly only a block problem, where our sleep is always
uninterruptible. Unless there are similar hacks elsewhere in the kernel
that I'm not aware of?

-- 
Jens Axboe